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The pure and carbon (C)-doped MgB2 thin films were fabricated on Al2O3 (0001) substrates at a temperature of 650 °C by using hot-filament-assisted hybrid physical–chemical vapor deposition technique. The Tc value for pure MgB2 film is 38.5 K, while it is between 30 and 35 K for carbon-doped MgB2 films. Expansion in c-axis lattice parameter was observed with increase in carbon doping concentration which is in contrast to carbon-doped MgB2 single crystals. Significant enhancement in the critical current density was obtained for C-doped MgB2 films as compared to the undoped MgB2 film. This enhancement is most probably due to the incorporation of C into MgB2 and the high density of grain boundaries, both help in the pinning of vortices and result in improved superconducting performance.